Changes in the Rate of Expansion over Time

Hubble Spies Most Distant Supernova Ever Seen

Using NASA's Hubble Space Telescope, astronomers pinpointed a blaze of light from the farthest supernova ever seen, a dying star that exploded 10 billion years ago. The detection and analysis of this supernova, called 1997ff, is greatly bolstering the case for the existence of a...

Supernova 1997ff's Cosmic Neighborhood

Home Galaxy of Supernova 1997ff

The Dying Star, Supernova 1997ff

The Expanding Universe

This diagram shows how the universe slowed down and then revved up since the Big Bang. The concentric red circles denote that galaxies are migrating apart at a slower rate during the first half of the cosmos. Than a mysterious dark force overcame gravity and began pushing...

Expansion of the Universe Over Time

This graph plots the size of the universe over time as measured by the Hubble telescope observations of exploding stars, called supernovas, at various distances from Earth. Hubble's study of exploding stars several light-years from Earth [white objects at far right of curve] set...

Composition of the Cosmos

This diagram shows the ingredients that make up the universe. Astronomers now realize that the universe's main ingredient is "dark energy," a mysterious form of energy that exists between galaxies. The next largest constituent is dark matter, which is an unknown form of matter....

Composition of the Universe

Illustration of Supernova in an Elliptical Galaxy

Illustration of Expanding Universe (Concentric Rings)

Illustration of Image Subtraction

Illustration of Diming of Light by Distance

Zoom out from SN1997f to Big Dipper

Animation of Supernova Explosion

Illustration of Supernova Image, Light Curve, and Spectrum

Interview with Dr. Adam Riess: Part 1

Interview with Dr. Adam Riess: Part 2

Interview with Dr. Ronald Gilliland: Part 1

Interview with Dr. Ronald Gilliland: Part 2

Space Science Update: Blast from the Past (Webcast)